This is a complete vacuum chamber kit. The single stage series of the single-stroke oil-rotating-vane vacuum pumps and the two stage series of the double-stroke oil-rotating vane vacuum pumps are the equipments for obtaining vacuum by pumping the gases from sealed containers, especially suitable for the pumping work for cold-producing maintenance, medical appliances printing machinery, vacuum packing, gas-analysis and hot-forming plastics. And they can also be used as the fore-stroke pumps of all kinds of high-vacuum equipments. So don't hesitate to take it home, it's quite useful!